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Gratzel's dye-sensitized solar cells (DSSCs) can readily convert sunlight into electricity, attracting considerable attention of global scientists. The fabrication efficiency of DSSCs was greatly limited by the slow fabrication (∼3.5-24 h) of quasi-solid (QS) electrolytes to date. In this study, novel composites of SiO2 aerogel with graphene (GR), multi-walled carbon nanotubes, or polyaniline were proposed in the fabrication of QS-state electrolytes. The morphology of these composites was characterized. The gels with SiO2 aerogels as QS electrolytes of DSSCs can be rapidly cured in ∼3 s. Using the screen-printing technology, these QS electrolytes can be readily utilized to construct the QS-DSSC to provide high efficiency and great stability. The photovoltaic parameters and interfacial charge-transfer resistances of the QS-DSSC incorporated with our synthetic composites were investigated in detail. Specifically, the SiO2 aerogel composed of GR (SiO2@GR) as a gel can greatly improve the performance of QS-DSSCs up to 8.25%. It is likely that these SiO2 aerogel composite electrolytes could provide a rapid curing process in the preparation of QS-state DSSCs, which might be useful to promote the development of DSSCs for future industrialization.

Phase change microcapsule refers to embedding phase change material as core material in the polymer wall material, and the latent heat possessed by the phase change material can be used to store and release. Meanwhile, phase change inks can be obtained by combining the microcapsules with inks in a certain proportion. In this study, phase change microcapsules with paraffin as the core material and melamine-formaldehyde resin as the wall material were synthesized by in-situ polymerization. The structure and performance of phase change microcapsules were characterized by differential scanning calorimetry and scanning electron microscope. At the same time, the phase change inks were obtained by formulating phase change microcapsules, binders, colorants and other materials at a certain ratio, and the printability of microcapsule inks was studied. The results show that the phase change microcapsules have good heat storage performance, and the phase change inks can be transferred to the surfaces of different flexible substrates by screen printing process. Finally, the functional printed products with phase change thermal insulation and patterning effects were obtained.

Functional microcapsule refers to a small container in which solid, liquid or gas are wrapped by natural or synthetic polymer materials to form a core-shell structure. Meanwhile, the corresponding functional ink can be obtained by combining functional microcapsule with ink. In this study, thermal expansion and aromatic slow-release functional microcapsules were formulated at a certain ratio with colorants and binders to obtain a composite microsphere ink with aromatic expansion effects. Based on this, the functional microcapsule ink is transferred to five kinds of different flexible printing substrates such as cotton, non-woven fabric, kraft paper, offset paper and coated paper by screen printing, and the impact of binder on ink printability is mainly investigated. Moreover, the surface morphology, foaming height, adhesion of printed products and thermal stability of printing ink were characterized by laser confocal microscope, thickness gauge and thermogravimetric analyzer. At the same time, the printing effects of functional microcapsule ink on different substrates were evaluated and the ink formula was adjusted. Finally, a functional printed product with long-lasting fragrance and three-dimensional effect is obtained.

Dye-sensitized solar cells (DSSCs) have the advantages of low cost, long life and no pollution. In recent years, DSSCs have rapidly developed into solar cells with commercial application prospects. Photoanodes have a critical impact on the performance of DSSCs. In this paper, photoanodes were prepared by screen printing. The size of titanium oxide, number of screen printing layers, mesh number in photoanode were studied. The surface thickness was observed by laser confocal microscopy, and the most suitable screen printing conditions were selected according to the photoelectric conversion efficiency of dye-sensitized solar cells. The researchon the preparation of DSSCs by screen printing provides an effective way for large-area industrial preparation of DSSCs.

Thermal expansion microcapsules (TEMs) are widely used in various fields due to their unique structures. In recent years, TEMs have attracted much attention and have broad market application prospects. In this study, thermally expandable microcapsules with a core–shell structure were prepared by suspension polymerization using acrylonitrile (AN), methyl methacrylate (MMA), and methyl acrylate (MA) as monomers and low-boiling alkane as the core material. Through particle size analysis, morphology test, thermal analysis and other methods, the effects of core material types, single core material and mixed core material, dispersion system on the microcapsule structure, particle size distribution, and expansion properties were compared. Moreover, the core material with a content of 35% can make the expansion ratio of the microcapsules up to 4 times. The expansion performance of the microcapsules with a mixture of isopentane and isooctane (ratio 1:1) as the core material was increased by 27% compared with that of a single core material. In addition, comparing with colloidal SO2/PVP dispersant, the expansion ratio of the microcapsules with magnesium hydroxide as the dispersant was increased by 20%. Finally, the optimized method for preparing thermally expandable microcapsules was obtained.